Sumitomo Electric Developed WiMAX Remote Radio Head

TOKYO--(BUSINESS WIRE)--Sumitomo Electric Industries, Ltd. (Tokyo:5802) (ISIN:JP3407400005) has currently succeeded in the development of a WiMAX remote radio head (RRH) capable of transmitting and receiving signals on up to four channels over a wide frequency range from 2.5 to 2.7 GHz.

In recent years, the number of cellular phone and other wireless base stations with a new design scheme has increased. More specifically, a power amplifier is relocated from a base station inside a building to beneath an antenna outside as an independent RRH unit. This unit is linked to a base station by a fiber-optic cable, providing more options for base station placement. Furthermore, locating the amplifier close to an antenna reduces transmission loss, thereby saving a large amount of electricity that would be wasted in a conventional power amplifier.

Today there is an emerging market for the RRH. In response to this trend, Sumitomo Electric has developed an RRH for WiMAX, a high-profile next generation broad band technology, by fully utilizing its original technology accumulated in the cell phone repeater manufacturing and other wireless communications fields. The company is now moving ahead to the mass production of the RRH.

To maximize the effect of the WiMAX, interference of radio waves must be avoided in urban areas with full of antennas, while a single base station needs to provide a wider network coverage in suburban or depopulated regions. Our RRH contributes to more flexible layout of base stations owing to the following features:

(1)	Compatible with multi-antenna systems for four transmitting/receiving channels
	Our WiMAX RRH integrates four transmitting and receiving channels into the single compact case and is suitable for the state of art multi-antenna systems. The multi-antenna systems enable the base station to avoid the radio interference, to enhance the throughput and to extend the coverage.
(2)	Covering a wide frequency range from 2.5 to 2.7 GHz
	The radio frequency usually varies depending on operators and services. Our RRH employs a power amplifier capable of operating over a wide frequency band from 2.5 to 2.7 GHz, allowing the users to save extra costs for development, maintenance and installation.
(3)	Adopting an optical interface
	Our RRH adopts an optical interface that has becoming a global standard.
(4)	Compact, lightweight, and power-saving
	A highly efficient power amplifier, used in combination with our original pre-distortion technique, improves the energy efficiency of the RRH. Requiring no cooling fans, the RRH has become increasingly compact, and thus easily mounted on a pole and other outside places without additional reinforcement work. The maintenance is also simplified.
*	WiMAX, or Worldwide Interoperability for Microwave Access, is a wireless broadband system based on the IEEE (Institute of Electrical and Electronics Engineers) 802.16 standard.
*	“WiMAX” is a trade mark or registered trade mark of the WiMAX Forum in the United States and some other countries.

About Sumitomo Electric

Sumitomo Electric Industries, Ltd. designs, manufactures and sells optical fiber, cable and components, advanced electronic devices, and automotive parts. Through a successful strategy of research and diversification, Sumitomo Electric has become one of the world’s leading companies at the forefront of the revolution in information and communications. Sumitomo Electric’s world-class research and manufacturing capabilities in optical technology continue to expand and strengthen the product portfolio while maintaining industry leading levels of reliability. The company has operations around the world in more than 30 countries and employs 150,000 people. Sumitomo Electric reported group net sales of $23 billion for the year ended March 2009. http://global-sei.com